promise

问题 I receive events on-the-fly in the correct order in which I want to process them after another (as well on-the-fly - so don't "store" them first). The following example is not going to work as the function someEventOccured() could be called multiple times in a very close timespan. Thus, the execution of handleEvent would overlap in time (which I don't want). As I am writing to a file in handleEvent() I cannot have simultaneously execute the function and need to maintain the order... async

问题 I receive events on-the-fly in the correct order in which I want to process them after another (as well on-the-fly - so don't "store" them first). The following example is not going to work as the function someEventOccured() could be called multiple times in a very close timespan. Thus, the execution of handleEvent would overlap in time (which I don't want). As I am writing to a file in handleEvent() I cannot have simultaneously execute the function and need to maintain the order... async

问题 I've created a lambda and cloud formation template which grants a lambda access to the parameter store and secrets manager. When I test the lambda I have the following functions outside of the export.handler function: function getParameterFromStore(param){ let promise = new Promise(function(resolve, reject){ console.log('++ ' + param.Path); servmgr.getParametersByPath(param, function(err, data){ if(err){ reject(console.log('Error getting parameter: ' + err, err.stack)); } else { resolve(data)

问题 I've created a lambda and cloud formation template which grants a lambda access to the parameter store and secrets manager. When I test the lambda I have the following functions outside of the export.handler function: function getParameterFromStore(param){ let promise = new Promise(function(resolve, reject){ console.log('++ ' + param.Path); servmgr.getParametersByPath(param, function(err, data){ if(err){ reject(console.log('Error getting parameter: ' + err, err.stack)); } else { resolve(data)

问题 I have a code segment that looks like this: async function autoScroll(page, maxDate = null) { await page.evaluate(async () => { await new Promise(async (resolve, reject) => { try { const scrollHeight = document.body.scrollHeight; let lastScrollTop = 0; const interval = setInterval(async () => { window.scrollBy(0, scrollHeight); const scrollTop = document.documentElement.scrollTop; let lastDate = null; if (maxDate) { const html = new XMLSerializer().serializeToString(document.doctype) +

问题 I have a code segment that looks like this: async function autoScroll(page, maxDate = null) { await page.evaluate(async () => { await new Promise(async (resolve, reject) => { try { const scrollHeight = document.body.scrollHeight; let lastScrollTop = 0; const interval = setInterval(async () => { window.scrollBy(0, scrollHeight); const scrollTop = document.documentElement.scrollTop; let lastDate = null; if (maxDate) { const html = new XMLSerializer().serializeToString(document.doctype) +

问题 When using Javascript promises, I ran into this weird behavior. Consider the following code: var Q = require('q'); var d1 = Q.defer(); var d2 = Q.defer(); compare(d1.promise, d2.promise); d1.resolve(3); d2.resolve(3); function compare(a, b) { Q.all([a,b]).then(function(results) { console.log('a: ' + a + ' b: ' + b); var result = (a == b)? 1: -1; console.log(result); }); } When you run this code, you get -1. I realize that I am not evaluating the results variable being passed in to the

问题 I executed following code with Node.js v10.15.0 Promise.resolve() .then(() => console.log('A')) .then(() => console.log('B')) .then(() => console.log('C')) setImmediate(() => console.log('IMMEDIATE')) Promise.resolve() .then(() => console.log('D')) .then(() => console.log('E')) .then(() => console.log('F')) As there is no asynchronous code involved in the fullfilled functions i expected following output A B C D E F IMMEDIATE but i got... A D B E C F IMMEDIATE As far as i understand the

问题 There are three buttons: Clicking the first Request HTTP Data As Promise button gets its HTTP response as a Promise . The second Request HTTP Data As Observable button gets its response as an Observable . Both these buttons get their responses using asynchronous response mechanism. Now, I would like the third Request HTTP Data and Wait button to get a synchronous response. I would like it to wait for the http service to return the HTTP response. How could it be done? Here is the link to the

问题 There are three buttons: Clicking the first Request HTTP Data As Promise button gets its HTTP response as a Promise . The second Request HTTP Data As Observable button gets its response as an Observable . Both these buttons get their responses using asynchronous response mechanism. Now, I would like the third Request HTTP Data and Wait button to get a synchronous response. I would like it to wait for the http service to return the HTTP response. How could it be done? Here is the link to the